What rule applies at the first nūn sākinah in «لَيُنْبَذَنَّ»?

Al-Māʿūn and Al-Humazah: Applied Assimilation, Concealment, Madd and Hāʾ Rules

• Mīm concealment because mīm follows
• Iqlāb, because bāʾ follows
• Throat iẓhār because ʿayn follows
• Non-nasal idghām because lām follows